System and method to conduct idle mode paging channel monitoring within a cellular wireless network

ABSTRACT

A method and system to determine when a wireless terminal has been paged by a servicing base station. An encoded paging burst is received on a paging channel and then decoded to produce a decoded paging burst. The decoded paging burst is processed to determine if it is a null page. When the encoded paging burst is a null page, it is processed to produce a null page pattern. The wireless terminal may then enter a sleep mode or reduced functionality mode for a predetermined period of time. The wireless terminal awakes from the sleep mode to receive additional encoded paging bursts. Processing the additional encoded paging bursts produces a processed encoded paging burst, which is compared to the null page pattern. When compared favorably, the encoded paging burst is considered a null page, allowing the wireless terminal to re-enter the sleep mode without fully decoding the paging burst.

CROSS REFERENCES TO RELATED APPLICATIONS

This patent application is a continuation of and claims priority to U.S.patent application entitled SYSTEM AND METHOD TO CONDUCT IDLE MODEPAGING CHANNEL MONITORING WITHIN A CELLULAR WIRELESS NETWORK, having anapplication Ser. No. 11/494,423 and a filing date of Jul. 27, 2006;which application is a continuation application of U.S. patentapplication entitled SYSTEM AND METHOD TO CONDUCT IDLE MODE PAGINGCHANNEL MONITORING WITHIN A CELLULAR WIRELESS NETWORK, having anapplication Ser. No. 10/749,661 and a filing date of Dec. 31, 2003, nowU.S. Pat. No. 7,107,080; as well as a continuation application of U.S.patent application entitled SYSTEM AND METHOD TO EXTRACT UPLINK STATUSFLAG BITS IN A CELLULAR WIRELESS NETWORK, having an application Ser. No.10/749,492 and a filing date of Dec. 31, 2003, now U.S. Pat. No.7,342,956; which are all incorporated herein by reference for allpurposes.

The 10/749,661 and 10/749,492 patent applications also claim priority toU.S. Provisional Application having a provisional application No.60/478,922, filed Jun. 16, 2003; which is also incorporated herein byreference for all purposes.

BACKGROUND

1. Technical Field

The present invention relates generally to cellular wirelesscommunication systems; and more particularly to the determining when aservicing base station has paged a wireless terminal.

2. Related Art

Cellular wireless communication systems support wireless communicationservices in many populated areas of the world. While cellular wirelesscommunication systems were initially constructed to service voicecommunications, they are now called upon to support data communicationsas well. The demand for data communication services has exploded withthe acceptance and widespread use of the Internet. While datacommunications have historically been serviced via wired connections,cellular wireless users now demand that their wireless units alsosupport data communications. Many wireless subscribers now expect to beable to “surf” the Internet, access their email, and perform other datacommunication activities using their cellular phones, wireless personaldata assistants, wirelessly linked notebook computers, and/or otherwireless devices. The demand for wireless communication system datacommunications will only increase with time. Thus, cellular wirelesscommunication systems are currently being created/modified to servicethese burgeoning data communication demands.

Cellular wireless networks include a “network infrastructure” thatwirelessly communicates with wireless terminals within a respectiveservice coverage area. The network infrastructure typically includes aplurality of base stations dispersed throughout the service coveragearea, each of which supports wireless communications within a respectivecell (or set of sectors). The base stations couple to base stationcontrollers (BSCs), with each BSC serving a plurality of base stations.Each BSC couples to a mobile switching center (MSC). Each BSC alsotypically directly or indirectly couples to the Internet.

In operation, each base station communicates with a plurality ofwireless terminals operating in its cell/sectors. A BSC coupled to thebase station routes voice communications between the MSC and a servingbase station. The MSC routes voice communications to another MSC or tothe PSTN. Typically, BSCs route data communications between a servicingbase station and a packet data network that may include or couple to theInternet. Transmissions from base stations to wireless terminals arereferred to as “forward link” transmissions while transmissions fromwireless terminals to base stations are referred to as “reverse link”transmissions. The volume of data transmitted on the forward linktypically exceeds the volume of data transmitted on the reverse link.Such is the case because data users typically issue commands to requestdata from data sources, e.g., web servers, and the web servers providethe data to the wireless terminals.

Wireless links between base stations and their serviced wirelessterminals typically operate according to one (or more) of a plurality ofoperating standards. These operating standards define the manner inwhich the wireless link may be allocated, setup, serviced and torn down.One popular cellular standard is the Global System for Mobiletelecommunications (GSM) standard. The GSM standard, or simply GSM, ispredominant in Europe and is in use around the globe. While GSMoriginally serviced only voice communications, it has been modified toalso service data communications. In GSM, wireless terminals areinformed of the need to service incoming communications via pages frombase stations to the wireless terminals. GSM General Packet RadioService (GPRS) operations and the Enhanced Data rates for GSM (orGlobal) Evolution (EDGE) operations coexist with GSM by sharing thechannel bandwidth, slot structure, and slot timing of the GSM standard.GPRS operations and EDGE operations may also serve as migration pathsfor other standards as well, e.g., IS-136 and Pacific Digital Cellular(PDC).

To conserve power, the wireless terminal may sleep when not activelycommunicating with a servicing base station. However, to ensure nocommunications are missed, the wireless terminal awakens periodically toreceive a page burst that indicates if the wireless terminal mustservice a communication from the servicing base station. To make thisdetermination, the wireless terminal typically expends significantbattery power and processing resources to decode the page burst and todetermine whether the wireless terminal was paged. Thus, there exists aneed for wireless terminals that can quickly and efficiently identifywhether it has been paged without unnecessarily consuming the resourcesof the wireless terminal.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a method and system to determine when awireless terminal has been paged by a servicing base station thatsubstantially meets the above-described needs among others. The methodbegins with an encoded paging burst being received on a paging channeland then decoded to produce a decoded paging burst. The decoded pagingburst is processed to determine if it is a null page. When the encodedpaging burst is a null page, it is processed to produce a null pagepattern. The wireless terminal may then enter a sleep mode or reducedfunctionality mode for a predetermined period of time. The wirelessterminal awakes from the sleep mode to receive additional encoded pagingbursts. Processing the additional encoded paging bursts produces aprocessed encoded paging burst, which is compared to the null pagepattern. When compared favorably, the encoded paging burst is considereda null page, allowing the wireless terminal to re-enter the sleep modewithout fully decoding the paging burst. However, when the comparison isunfavorable it may be necessary to fully decode the encoded pagingburst.

In additional embodiments, the null page pattern as well as theprocessed encoded paging bursts, are made up of a set of soft decisions.Each soft decision of the null page pattern corresponds to a softdecision that is within the process encoded paging bursts. This allows aone-to-one comparison to produce a set of comparisons between theencoded paging burst and the null page pattern. If the number offavorable comparisons exceeds a comparison threshold, the wirelessterminal may then act as if the paging burst is a null page. Similarly,if the number of comparisons does not exceed a comparison threshold, thecomparison is unfavorable in which case the wireless terminal acts as ifit had been paged. Additionally, processing the encoded paging burst mayinvolve equalizing to produce a proper set of soft decision bits.

Another embodiment provides a wireless terminal that performs theseoperations. This wireless terminal has a Radio Frequency (RF) front-end,a baseband processor operably coupled to the RF front-end, and anenCOding/DECoding (CODEC) processing module operably coupled to thebaseband processor. During a first time interval the RF front-end,baseband processor, and CODEC processing module operate in combinationto receive an encoded paging burst on a paging channel. The combinationor its elements then decodes the encoded paging burst to produce adecoded paging burst. It is determined whether or not the decoded pagingburst contains a null page for the wireless terminal. The null page isfurther processed to produce a null page pattern, which may be storedfor future comparisons. Additionally, at the end of the first timeperiod when the decoded paging burst corresponds to a null page for thewireless terminal, the wireless terminal enters a sleep mode for a sleepperiod. During a second period of time, the RF front-end, basebandprocessor, and CODEC processing module awaken from the sleep mode at theexpiration of the sleep mode period to receive additional encoded pagingbursts. These additional encoded paging bursts are processed by the RFfront-end, baseband processor, and CODEC processing module to produce aprocessed encoded paging burst. Then, these elements compare theprocessed encoded paging bursts to the null page pattern. When thecomparison is favorable, one can consider the additional encoded burstto be a null page.

Another embodiment of the present invention also provides a wirelessterminal. This wireless terminal has a RF front-end operatively coupledto a baseband processor. These elements take on the function of thepreviously identified CODEC processing module. The RF front-end and thebaseband processor operate to receive an encoded paging burst on apaging channel and decode that encoded paging burst to produce a decodedpaging burst. The decoded paging burst is further processed to determineif the decoded paging burst contains a null page for the wirelessterminal. When the decoded paging burst contains a null page for thewireless terminal the encoded paging burst is processed to produce anull page pattern. After this processing, the baseband processor and RFfront-end direct the wireless terminal to enter a sleep mode for a sleepperiod of time. At the expiration of a sleep mode period, the RFfront-end and the baseband processor awaken from the sleep mode toreceive an additional encoded paging burst. This paging burst isprocessed to produce a processed encoded paging burst. The processedencoded paging burst may be compared to the null page pattern and whenthe comparison is favorable determine that the additional encoded pagingburst is a null page. In the instance where the additional encodedpaging burst is a null page, the RF front-end and baseband processordirect the wireless terminal to re-enter the sleep mode upon thefavorable comparison. However, when the comparison is unfavorable thebaseband processor operates to decode the processed encoded pagingburst.

Other features and advantages of the present invention will becomeapparent from the following detailed description of the invention madewith reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a system diagram illustrating a portion of a cellular wirelesscommunication system that supports wireless terminals operatingaccording to the present invention;

FIG. 2 is a block diagram functionally illustrating a wireless terminalconstructed according to the present invention;

FIG. 3 is a block diagram illustrating in more detail the wirelessterminal of FIG. 2, with particular emphasis on the digital processingcomponents of the wireless terminal;

FIG. 4A is a block diagram illustrating the formation of paging channeldownlink transmissions;

FIG. 4B is a timeline illustrating the receipt and decoding of pagingbursts particularly comparing full decoding to partial decodingaccording to the present invention;

FIG. 5 is a flow chart illustrating operation of a wireless terminal inreceiving and processing a paging burst according to the presentinvention; and

FIG. 6 is a flow chart illustrating subsequent operations of thewireless terminal of FIG. 5 in receiving and processing a subsequentpaging burst according to the present invention.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 is a system diagram illustrating a portion of a cellular wirelesscommunication system 100 that supports wireless terminals operatingaccording to the present invention. The cellular wireless communicationsystem 100 includes a Mobile Switching Center (MSC) 101, Serving GPRSSupport Node/Serving EDGE Support Node (SGSN/SESN) 102, base stationcontrollers (BSCs) 152 and 154, and base stations 103, 104, 105, and106. The SGSN/SESN 102 couples to the Internet 114 via a GPRS GatewaySupport Node (GGSN) 112. A conventional voice terminal 121 couples tothe PSTN 1110. A Voice over Internet Protocol (VoIP) terminal 123 and apersonal computer 125 couple to the Internet 114. The MSC 101 couples tothe Public Switched Telephone Network (PSTN) 110.

Each of the base stations 103-106 services a cell/set of sectors withinwhich it supports wireless communications. Wireless links that includeboth forward link components and reverse link components supportwireless communications between the base stations and their servicedwireless terminals. These wireless links support digital datacommunications, VoIP communications, and other digital multimediacommunications. The cellular wireless communication system 100 may alsobe backward compatible in supporting analog operations as well. Thecellular wireless communication system 100 supports the Global Systemfor Mobile telecommunications (GSM) standard and also the Enhanced Datarates for GSM (or Global) Evolution (EDGE) extension thereof. Thecellular wireless communication system 100 may also support the GSMGeneral Packet Radio Service (GPRS) extension to GSM. However, thepresent invention is also applicable to other standards as well, e.g.,TDMA standards, CDMA standards, etc. In general, the teachings of thepresent invention apply to digital communications that combine AutomaticRepeat ReQuest (ARQ) operations at Layer 2, e.g., LINK/MAC layer withvariable coding/decoding operations at Layer 1 (PHY).

Wireless terminals 116, 118, 120, 122, 124, 126, 128, and 130 couple tothe cellular wireless communication system 100 via wireless links withthe base stations 103-106. As illustrated, wireless terminals mayinclude cellular telephones 116 and 118, laptop computers 120 and 122,desktop computers 124 and 126, and data terminals 128 and 130. However,the cellular wireless communication system 100 supports communicationswith other types of wireless terminals as well. As is generally known,devices such as laptop computers 120 and 122, desktop computers 124 and126, data terminals 128 and 130, and cellular telephones 116 and 118,are enabled to “surf” the Internet 114, transmit and receive datacommunications such as email, transmit and receive files, and to performother data operations. Many of these data operations have significantdownload data-rate requirements while the upload data-rate requirementsare not as severe. Some or all of the wireless terminals 116-130 aretherefore enabled to support the GPRS and/or EDGE operating standard aswell as supporting the voice servicing portions the GSM standard.

FIG. 2 is a block diagram functionally illustrating a wireless terminal200 constructed according to the present invention. The wirelessterminal 200 of FIG. 2 includes an RF transceiver 202, digitalprocessing components 204, and various other components contained withina housing. The digital processing components 204 includes two mainfunctional components, a physical layer processing, speech COder/DECoder(CODEC), and baseband CODEC functional block 206 and a protocolprocessing, man-machine interface functional block 208. A Digital SignalProcessor (DSP) is the major component of the physical layer processing,speech COder/DECoder (CODEC), and baseband CODEC functional block 206while a microprocessor, e.g., Reduced Instruction Set Computing (RISC)processor, is the major component of the protocol processing,man-machine interface functional block 208. The DSP may also be referredto as a Radio Interface Processor (RIP) while the RISC processor may bereferred to as a system processor. However, these naming conventions arenot to be taken as limiting the functions of these components.

The RF transceiver 202 couples to an antenna 203, to the digitalprocessing components 204, and also to a battery 224 that powers allcomponents of the wireless terminal 200. The physical layer processing,speech COder/DECoder (CODEC), and baseband CODEC functional block 206couples to the protocol processing, man-machine interface functionalblock 208 and to a coupled microphone 226 and speaker 228. The protocolprocessing, man-machine interface functional block 208 couples to aPersonal Computing/Data Terminal Equipment interface 210, a keypad 212,a Subscriber Identification Module (SIM) port 213, a camera 214, a flashRAM 216, an SRAM 218, a LCD 220, and LED(s) 222. The camera 214 and LCD220 may support either/both still pictures and moving pictures. Thus,the wireless terminal 200 of FIG. 2 supports video services as well asaudio services via the cellular network.

FIG. 3 is a block diagram illustrating in more detail the wirelessterminal of FIG. 2, with particular emphasis on the digital processingcomponents of the wireless terminal. The digital processing components204 include a system processor 302, a baseband processor 304, and aplurality of supporting components. The supporting components include anexternal memory interface 306, MMI drivers and I/F 308, a video I/F 310,an audio I/F 312, a voice band CODEC 314, auxiliary functions 316, amodulator/demodulator 322, ROM 324, RAM 326 and a plurality ofprocessing modules. In some embodiments, the modulator/demodulator 322is not a separate structural component with these functions beingperformed internal to the baseband processor 304.

The processing modules are also referred to herein as accelerators,co-processors, processing modules, or otherwise, and include auxiliaryfunctions 316, an equalizer module 318, an encoder/decoder module 320,and an Incremental Redundancy (IR) processing module 328. Theinterconnections of FIG. 3 are one example of a manner in which thesecomponents may be interconnected. Other embodiments supportadditional/alternate couplings. Such coupling may be direct, indirect,and/or may be via one or more intermediary components.

RAM and ROM service both the system processor 302 and the basebandprocessor 304. Both the system processor 302 and the baseband processor304 may couple to shared RAM 326 and ROM 324, couple to separate RAM,coupled to separate ROM, couple to multiple RAM blocks, some shared,some not shared, or may be served in a differing manner by the memory.In one particular embodiment, the system processor 302 and the basebandprocessor 304 coupled to respective separate RAMs and ROMs and alsocouple to a shared RAM that services control and data transfers betweenthe devices. The processing modules 316, 318, 320, 322, and 328 maycoupled as illustrated in FIG. 3 but may also coupled in other mannersin differing embodiments.

The system processor 302 services at least a portion of a servicedprotocol stack, e.g., GSM/GPRS/EDGE protocol stack. In particular thesystem processor 302 services Layer 1 (L1) operations 330, a portion ofIncremental Redundancy (IR) GSM protocol stack operations 332 (referredto as “IR control process”), Medium Access Control (MAC) operations 334,and Radio Link Control (RLC) operations 336. The baseband processor 304in combination with the modulator/demodulator 322, RF transceiver,equalizer module 318, and/or encoder/decoder module 320 service thePhysical Layer (PHY) operations performed by the digital processingcomponents 204.

FIG. 4A depicts the various stages associated with forming andinterpreting paging channel (PCH) downlink transmissions. The originalpages for the individual wireless terminals or mobile stations areinitially divided into a series of pages to be transmitted according toa predetermined schedule to the wireless terminals. This predeterminedschedule allows the individual wireless terminals, when not activelytransmitting, to enter a sleep mode and merely awaken when it isnecessary to receive their respective page bursts. As shown here, theoriginal page undergoes two stages of encoding. First, the originalpages undergo a block coding operation that is typically referred to asouter encoding. The block coding stage, allows for the detection oferrors within the data block. In addition, the Data blocks may besupplemented with tail bits or block code sequence. Since Block Codingis the first or external stage of channel coding, the block code is alsoknown as an external or outer encoding scheme. Typically, two kinds ofcodes are used, a cyclic redundancy check (CRC) or a Fire Code. The FireCodes allow for either error correction or error detection. Errordetection with the Fire Code, verifies connectivity.

Next, the pages undergo a second level of encoding that typically is aconvolutional coding referred to as inner encoding. The pages may beoptionally interleaved to form paging bursts. These paging bursts arewhat the wireless terminal receives according to the predeterminedschedule.

FIG. 4B is a timeline illustrating the receipt and decoding of pagingbursts particularly comparing full decoding to partial decodingaccording to the present invention. Illustrated in FIG. 4B are a seriesof paging bursts 400 that are received according to paging groupsreceived approximately every 0.5 to 2.0 seconds. The paging bursts carryeither a page or a null page for each wireless terminal assigned to acorresponding paging group. When carrying a page, the paging burst 400signal the wireless terminal to respond to the servicing base station.This may involve servicing a voice call, data or text. When the pagingburst 400 is sent, individual wireless terminals that are assigned tothe paging group awaken for a period of time indicated by the awakeportion of timeline 402 to receive the paging burst.

Typically, 4 paging bursts makeup every paging message and traditionallyall 4 paging bursts need to be received before decoding can begin. Bymaking use of the Null page template a sufficiently reliable indicationof whether or not the paging message contains any useful information forthe mobile can be obtained from only the 1st paging burst of the 4paging bursts without waiting the 4 paging bursts. If after receivingthe 1st paging burst and performing the null pattern match the result isinconclusive then the 2nd paging burst can be received and tested forconformity to the null paging message, and so on until all 4 bursts havebeen received. As one can appreciate, each paging burst which does nothave to be received over the air-interface provides measurable anduseful power consumption benefits. If all 4 paging bursts of the blockare received and decoded, this constitutes normal paging messagereception/decoding. The benefits result from reducing the time that theradio (RF) portion of the receiver is employed (receiving 1 or 2 burstsinstead of 4 bursts) and bypassing a large amount of unnecessarybaseband message decoding and further processing to understand thecontents of the message.

Timeline 402 shows that the wireless terminal's processors are eitherawake or asleep. When the wireless terminal awakens it may fully decodethe paging burst. Alternatively, according to the present invention,when there is a favorable pattern comparison between the paging burstand a null page pattern, the wireless terminal determines that thepaging burst is a null page. However, one should note that a null pagemight be required to be fully decoded. Time segments 404 and 406 showthat the time required to fully decode the paging burst is much greaterthan that required to merely perform a pattern comparison on theprocessed paging burst with an existing pattern. Therefore one canappreciate that the wireless terminal will remain awake much longer whena full decode of the paging burst is required. This means thatadditional power will be consumed and processing resources will beutilized to fully decode the paging burst when compared to merelyconducting a pattern comparison as indicated in block 406.

FIG. 5 is a flow chart illustrating operation of a wireless terminal inreceiving and processing a paging burst according to the presentinvention. The RF front end receives an encoded paging burst in step502. The RF front end then converts the encoded paging burst into abaseband signal for the baseband processor in step 504. In step 506, theRF front end then asserts an interrupt to the baseband processor thatcauses the baseband processor to receive and begin processing thebaseband signal containing the paging burst at step 508. The basebandprocessor pre-processes the encoded paging bursts in Step 510 andequalizes the pre-processed encoded paging bursts in Step 512 to producesoft decisions. Alternately, the equalizer module 318 equalizes thepre-processed encoded paging burst and interrupts the baseband processorto indicate that the equalizer operations are complete for the pagingburst. In this case, the baseband processor receives the soft decisionsfrom the equalizer module.

At Step 514 soft symbols of the encoded paging bursts are decoded. Thisdecoding may be performed by the baseband processor 304 or theEncoder/Decoder module 320. The decoding of step 514 corresponds to thecoding operations performed by the servicing base station in creatingthe paging burst. The decoded paging burst is evaluated at decisionpoint 516 to whether or not the page is a null page. If the paging burstis not a null page, in Step 518 the wireless terminal responds to thepage, which may include servicing a call.

If the page is a null page a null page pattern is produced at step 520.The null page pattern may simply be the soft decisions that wereproduced at step 512. Alternately, the soft decisions produced at step512 may be further processed to produce the null page pattern. Onetechnique for doing this processing involves concatenating the softdecisions into hard decisions and using the hard decisions as the nullpage pattern. Still another technique for determining the null pagepattern is to re-encode the decoded null page produced at step 514 toproduce the null page pattern. Using this technique, the encodingscheme(s) that is used by the base station to encode paging bursts mustbe known and used. The null page pattern is then stored in memory atstep 522. The wireless terminal may then re-enter the sleep mode for apredetermined period of time step 524.

FIG. 6 is a flow chart illustrating subsequent operations of thewireless terminal of FIG. 5 in receiving and processing a subsequentpaging burst according to the present invention. In FIG. 6, the RF frontend receives an encoded paging burst in Step 602, which the RF front endthen converts to a baseband signal in Step 604. An interrupt for thebaseband processor is issued in Step 606 in order to have the basebandprocessor receive and process the baseband signal in Step 608. Steps 610and 612 indicate preprocessing of the paging bursts and equalizing thepre-processed encoded paging burst. In Step 614 soft symbols of thepre-processed encoded paging bursts are compared to a null page pattern.The null page pattern stored at step 522 of FIG. 5 is compared to thesoft symbols of the pre-processed encoded paging bursts.

When the comparison at decision point 616 is favorable, the wirelessterminal enters or re-enters a sleep mode at Step 620 because thewireless terminal considers the paging burst to be a null page. When thecomparison at decision point 616 is not favorable it becomes necessaryto fully decode the soft symbols of the encoded paging bursts and thenrespond to the page or service call. These steps are achieved byreturning to Step 514 of FIG. 5.

As one of average skill in the art will appreciate, the term“substantially” or “approximately”, as may be used herein, provides anindustry-accepted tolerance to its corresponding term. Such anindustry-accepted tolerance ranges from less than one percent to twentypercent and corresponds to, but is not limited to, component values,integrated circuit process variations, temperature variations, rise andfall times, and/or thermal noise. As one of average skill in the artwill further appreciate, the term “operably coupled”, as may be usedherein, includes direct coupling and indirect coupling via anothercomponent, element, circuit, or module where, for indirect coupling, theintervening component, element, circuit, or module does not modify theinformation of a signal but may adjust its current level, voltage level,and/or power level. As one of average skill in the art will alsoappreciate, inferred coupling (i.e., where one element is coupled toanother element by inference) includes direct and indirect couplingbetween two elements in the same manner as “operably coupled”. As one ofaverage skill in the art will further appreciate, the term “comparesfavorably”, as may be used herein, indicates that a comparison betweentwo or more elements, items, signals, etc., provides a desiredrelationship. For example, when the desired relationship is that signal1 has a greater magnitude than signal 2, a favorable comparison may beachieved when the magnitude of signal 1 is greater than that of signal 2or when the magnitude of signal 2 is less than that of signal 1.

The foregoing description of a preferred embodiment of the invention hasbeen presented for purposes of illustration and description. It is notintended to be exhaustive or to limit the invention to the precise formdisclosed, and modifications and variations are possible in light of theabove teachings or may be acquired from practice of the invention. Theembodiment was chosen and described in order to explain the principlesof the invention and its practical application to enable one skilled inthe art to utilize the invention in various embodiments and with variousmodifications as are suited to the particular use contemplated. It isintended that the scope of the invention be defined by the claimsappended hereto, and their equivalents.

1. A method comprising: receiving an encoded paging burst on a pagingchannel for a wireless device; processing the encoded paging burst toobtain a plurality of soft symbols; and comparing the plurality of softsymbols to previously stored soft decisions of a null page pattern todetermine if the wireless device is to enter a reduced functionalitymode.
 2. The method of claim 1, wherein the reduced functionality modeis a sleep mode.
 3. The method of claim 1, wherein the reducedfunctionality mode is a sleep mode and if the comparing of the pluralityof soft symbols to the previously stored soft decisions results in athreshold certainty, then the wireless device enters the sleep modewithout further decoding the soft symbols.
 4. The method of claim 1,wherein the reduced functionality mode is a sleep mode and if thecomparing of the plurality of soft symbols to the previously stored softdecisions results in a threshold certainty, then the wireless devicere-enters the sleep mode without further decoding the soft symbols. 5.The method of claim 1, further comprising receiving an earlier encodednull page paging burst, decoding the null page paging burst to identifya null page, obtaining soft decisions of the null page and storing softdecisions as the null page pattern.
 6. The method of claim 1, furthercomprising awakening from an initial sleep mode to receive the encodedpaging burst.
 7. The method of claim 6, wherein if the comparing of theplurality of soft symbols to the previously stored soft decisions doesnot result in a threshold certainty, then the wireless device remains inan awake mode to decode the encoded paging burst.
 8. The method of claim1, wherein processing the encoded paging burst includes at leastequalizing the encoded paging burst to produce the plurality of softsymbols.
 9. An apparatus comprising: a radio frequency (RF) front end ofa wireless device to receive an encoded paging burst on a pagingchannel; and digital processing components coupled to the RF front endto digitally process the encoded paging burst, in which the digitalprocessing components obtain a plurality of soft symbols from theencoded paging burst and compares the plurality of soft symbols topreviously stored soft decisions of a null page pattern to determine ifthe wireless device is to enter a reduced functionality mode.
 10. Theapparatus of claim 9, wherein the reduced functionality mode is a sleepmode.
 11. The apparatus of claim 9, wherein the reduced functionalitymode is a sleep mode and if the comparison of the plurality of softsymbols to the previously stored soft decisions results in a thresholdcertainty, then the wireless device enters the sleep mode withoutfurther decoding the soft symbols.
 12. The apparatus of claim 9, whereinthe reduced functionality mode is a sleep mode and if the comparison ofthe plurality of soft symbols to the previously stored soft decisionsresults in a threshold certainty, then the wireless device re-enters thesleep mode without further decoding the soft symbols.
 13. The apparatusof claim 9, wherein the RF front end receives an earlier encoded nullpage paging burst and the digital processing components decode the nullpage paging burst to identify a null page, obtain soft decisions of thenull page and store soft decisions as the null page pattern.
 14. Theapparatus of claim 9, wherein the RF front end and the digitalprocessing components awaken from an initial sleep mode to receive theencoded paging burst.
 15. The apparatus of claim 14, wherein if thecomparison of the plurality of soft symbols to the previously storedsoft decisions does not result in a threshold certainty, then thewireless device remains in an awake mode to decode the encoded pagingburst.
 16. The apparatus of claim 9, wherein the digital processingcomponents equalize the encoded paging burst to produce the plurality ofsoft symbols.